[packagekit] yum, apt, smart and conary backends

[Richard Hughes]

Right, a ton of the backends are written in python. The new process and
simple IPC approach we've been using has been working okay, but now lots
of other projects are depending on PackageKit and we could do something
a little less copy/paste (and faster to init) for the python backends.

I'm thinking of linking in Python into a main process thread (so all IPC
is native) rather than using the standard out and in. We'll obviously
keep this for all the other backends, but I think we can justify pulling
in Python.h for speed and code reuse.

Something like http://docs.python.org/ext/extending-with-embedding.html
gives a good tutorial.

Has anyone got any experience with this? This should be a lot simpler to
use and test than the dbus backend (and no IPC) and loads quicker than
spawning a new process each time.

I've not decided if this is a good idea or not. Comments welcome.

Richard.